Rhinoceroses rest in the Kruger National Park near Nelspruit, South Africa in 2013 (Issouf Sanogoissouf/AFP/ Getty Images)

With back alley price tags jumping up as high as $45,000 per pound, illegal rhino horns are increasingly hot items on the international black market.

For the second time in six years, Irish smuggler Michael Hegarty stood in a U.S. federal courtroom to plead guilty to charges related to the rhino horn market. Last Friday in Miami, Hegarty, 40, admitted he paid $50,000 for a Chinese libation cup carved from the horn of an endangered black rhinoceros, then smuggled the item back to London in an attempt to sell it to a Hong Kong buyer.

The case not only notches a win for the U.S. government’s increased effort to tackle rhino smuggling — code-named “Operation Crash” — but provides a peek at the tireless international smuggling crews running the underground quarter of a billion dollar business for the horn, a product with a higher street value than diamonds or cocaine.

Rhinoceros horn is made from keratin, the same protein in animal hoofs, bird feathers, and human hair and fingernails. The rhino horn trade was banned by an international trade accord in 1977, according to Vice. A resurgent underground market, however, kicked in around 2009, when an unnamed “Vietnamese official” announced he cured liver cancer by eating rhino horn.

Today, in Asian countries — particularly among wealthier buyers in China, Vietnam and Taiwan — rhino horn is ingested for a range of medical ailments, from hangover cures to aphrodisiacs.

The illicit demand has hit the hardest in South Africa, the home of 70 percent of the world’s remaining 29,500 rhinos, National Geographic reported last year. Poaching has increased dramatically: The country’s Department of Environmental Affairs reported that 1,175 rhinos were killed by poachers in 2015. In 2007, only 13 were killed, according to Vice.

Among the earliest organizations to realize the potential of the market were Irish Travelers from Rathkeale, a town about 22-miles from Limerick. Vice reported:

In his 2013 book, Gypsy EmpireSunday World crime journalist Eamon Dillon describes the Rathkeale Travellers as “willing to do business on any continent, moving quickly from one deal to the next, following the trail of euros, dollars, or pounds sterling.” In the last few years, members of the Rovers have been found attempting to pull the tarmacking scam on nuns in Italy, smuggling tobacco through Belgium, and selling dodgy generators in Australia.

In 2014, Edward Grace, a law enforcement official with the U.S. Fish and Wildlife Service told The Washington Post Rathkeale smugglers — eventually known as the Rathkeale Rovers — were selling antiques in Asia when they were clued into the rhino market.

“The Chinese and Vietnamese led them into the rhino trade,” Grace told The Post. “They told them, while you’re out buying these . . . antiques, keep an eye out for rhino horn, for which we will pay more than the price of gold.”

Rhinoceros horns on display in Hong Kong’s Customs and Excise Department Offices in 2011. (AFP/Getty Images)

Rathkeale Rovers have been tied by European authorities to museum break-ins where ancient rhino horn pieces were stolen. Members of the syndicate have also turned up in America: In 2012, The Post reported Rovers attempted to use fake documents to buy a trophy rhino horn at auction in Dallas and then resell the piece in New York.

In 2010, U.S. Fish and Wildlife officials set up two Irish nationals attempting to buy rhino horns in Colorado. The two men — Richard O’Brien and Michael Hegarty — were arrested after making the purchase for $17,618. “A search of the men’s criminal histories exposed them as members of a syndicate known as the Rathkeale Rovers,” The Post reported.

Hegarty eventually pleaded guilty to federal charges related to the sting; he was sentenced to six months in prison.

But his legal troubles continued after an April 2012 rhino horn buy.

According to a news release from the Justice Department, that month Hegarty and a co-conspirator traveled with a Miami resident to Rockingham, N.C. There, the men successfully bid on a Chinese libation cup made from rhino horn. After wiring $59,225 to the auction house, the men took possession of the cup in Coconut Grove, Fla., on May 2, 2012.

“The co-conspirator then smuggled the libation cup out of the United States in his luggage, and failed to declare the export of the rhino horn libation cup as required by law to the U.S. Fish & Wildlife Service and neither applied for nor obtained the permit required under the Endangered Species Act,” the Justice Department’s news release stated.

Hegarty was arrested in Belgium by Interpol and extradited to the United States His co-conspirator, Richard Sheridan is currently incarcerated in England on unrelated charges. Hegarty faces up to 10 years in prison and is due for sentencing Nov. 14.

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